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ChrisBennet ChrisBennet is offline
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Join Date: Aug 2001
Location: Nashua, NH USA
Posts: 8,164
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Quote:
Originally posted by sammyg2
I heard the DOT5 (silicone based) brake fluid is non-hydroscopic so that it does not absorbe moisture, but it feels ""spongy". Never used it, just what I've heard. Sounds like someone is telling us a story :-)
Normal brake fluid is hygroscopic (attracts moisture).
Silicone brake fluid is synthetic but sythetic fluid is not necessarily silicone. Castrol SynPower (and I'm guessing Motul 5.1) are non-silicone synthetics. They are referred to as a "DOT 5.1" fluids.
Silicone is non-hygroscopic which is nice because it can sit for years at a time in a brake system. This makes it great for Army trucks being stored for years for example.
Silicone has a couple of bad characteristics. It (supposedly) will trap moisture in a system that previously used "normal" brake fluid causing corrosion. It (supposedly) is also is harder to bleed. I guess the "champagne" bubbles tend stay suspended in it.
-Chris
Old 11-19-2002, 11:30 AM
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